地质通报2017，Vol.36Issue(10)：1698-1707,10.
辽北西丰地区宝兴岩体LA-ICP-MS锆石U-Pb年龄及岩石地球化学特征
LA-ICP-MS zircon U-Pb dating and geochemical characteris-tics of Baoxing rock mass in Xifeng area of northern Liaoning Province
摘要
Abstract
Located on the northern margin of North China Block, the Baoxing rock mass is mainly composed of granodiorite. Ac-cording to LA-ICP-MS zircon U-Pb dating, it was formed in Middle Triassic, with the 206Pb/238U age of 235.0±1.3Ma. The aver-age K2O/Na2O ratio is 1.07, indicating that the rocks belong to high-K calc-alkaline series. The rocks are enriched in LILE and de-pleted in HFSE, showing typical features of calc-alkaline series on an active continental margin. The average total amount of REE is 147×10-6, and the curve exhibits obvious right-inclined feature on REE distribution pattern, suggesting that the rocks are of the type of LREE enrichment and HREE depletion with medium negative Eu anomaly. According to the petrology, geochemistry and geo-chronology in combination with the tectonic evolution research on adjacent areas, lithospheric delamination occurred under the ex-tension in the study area, and then caused a large-scale magmatic activity in the Middle Triassic.关键词
中三叠世/LA-ICP-MS锆石U-Pb测年/宝兴岩体/花岗闪长岩/辽北地区/华北板块Key words
Middle Triassic/LA-ICP-MS zircon U-Pb dating/Baoxing rock mass/granodiorite/northern Liaoning Province/North China Block分类
天文与地球科学引用本文复制引用
彭游博,宋淑娥,刘锦,张文静,王恩德,赵辰..辽北西丰地区宝兴岩体LA-ICP-MS锆石U-Pb年龄及岩石地球化学特征[J].地质通报,2017,36(10):1698-1707,10.基金项目
中国地质调查局项目《辽东-吉南成矿带永吉—凤城地区地质矿产调查》(编号:DD20160049) （编号:DD20160049）
